PurgeThumbnailJob result = purgeThumbnailJob.expiry(-1000L);

        // Test method chaining
        assertSame(purgeThumbnailJob, result);
        // Test value was not changed
        assertEquals(originalExpiry, purgeThumbnailJob.getExpiry());
    }

    // Test expiry setter with small positive value
    public void test_expiry_smallPositiveValue() {